(E)-2-[2-(4-Chloro-benzyl-idene)hydrazin-1-yl]-4-{[3-(dimethyl-aza-nium-yl)prop-yl]amino}-quinazolin-1-ium bis-(perchlorate).

In the title compound, C(20)H(25)ClN(6) (2+)·2ClO(4) (-), the organic cation is roughly planar, as shown by the dihedral angle of 3.78 (3)° between the quinazoline and chloro-phenyl rings. The quinazoline ring is itself approximately planar, with an average deviation of 0.018 (4) Å. The organic cation adopts an E configuration with respect to the C= N double bond of the hyrazinyl group. The (dimethyl-aza-nium-yl)propyl-amino side chain is disordered over two sets of sites with occupancies of 0.768 (10) and 0.232 (10). In the crystal, two cations and four anions are linked by strong N-H⋯O hydrogen bonds. Weak C-H⋯O hydrogen bonds exist among these aggregates.